From conformons to human brains: an informal overview of nonlinear dynamics and its applications in biomedicine <s> Conclusion <s> We proposed a very simple new method of quantitative assessment of surface roughness and texture. We have combined methods that have been used in medicine (histopathology) with methods used in nonlinear time series analysis. A greyscale 2-D image of a 3-D surface is used for calculations of the surface fractal dimension which is a good measure of surface roughness. In the pre-processing step, the image is transformed into 1-D signals (“landscapes”) that are subsequently analyzed. The method draws from multiple disciplines and has multidisciplinary applications. One of the possible applications is quality assessment of nanosensors. The same methods of analysis may be used for processing of (bio)signals generated by these nanosensors. <s> BIB001 </s> From conformons to human brains: an informal overview of nonlinear dynamics and its applications in biomedicine <s> Conclusion <s> We propose a new very simple method to determine roughness of a surface of an implant material from its scanning electron microscopy (SEM) image. For this purpose we have combined a preprocessing method that has been used in histopathology with fractal method used in nonlinear time series analysis. In the pre-processing step the image is transformed into 1-D signals (‘landscapes’) that are subsequently analyzed. Our method draws from multiple disciplines and may find multidisciplinary applications. <s> BIB002
Until recently quantitative computerized EEG-signal analysis was based primarily on linear theory. But developments in nonlinear dynamics and deterministic chaos theory have considerably altered our perception and analysis of many complex systems, including the brain. Additional information extracted from EEG by methods of nonlinear analysis may increase the sensitivity of electrophysiological methods. BIB001 , and for SEM image analysis for roughness assessment of implant materials BIB002 . We are exploring and developing other nonlinear methods, in particular symbolic analysis methods (cf. [21,  ). Nonlinear dynamics methods may find application also in psychophysiology  . Our world is not governed by simple linear laws most of us were taught at school. If one man digs a ditch in one hour it does not mean that 60 men will dig the same ditch in one minute -this is obvious for everybody, even for those who do not know contemporary physics and mathematics. What in physics is called nonlinearity it is just stating the fact that elements forming a system do not act independently one from another -in the example above the system consists of one ditch and 60 men whose work is restricted by the size of the ditch. In biology and medicine two plus two often does not make four [37] -it is well known that the effect of a drug is not just simply proportional to its dose and interactions of different drugs are also extremely important. Chaos is revolutionary in that the overall approach requires us to adopt a different paradigm which, at times, may move us away from linear methods of data analysis.