In this book, recent developments in methodologies and novel results or information obtained are described by experts in each field, together with the biological and medical aspects of their applications. Here we summarize the content of the subsequent chapters, and their biomedical applications are appended as follows:

When a dilute polymer solution is quenched below the consolute point, the polymer chains collapse and chain aggregation occurs competitively owing to the intra- and intermolecular interactions between polymer segments. At very low concentrations, polymer chains collapse first (the coil-globule transition) and the collapsed chains aggregate, whereas at high concentrations, it is even more complex because of the entanglement of polymer chains. This is one of the most essential rheological events at the nanoscale and microscale in systems containing polymer molecules. In Chap. 2, the kinetics of chain aggregation and chain collapse in dilute polymer solutions are discussed using a typical system. The concepts are applied to the current topic of the aggregation of intrinsically disordered proteins. Studies on the coil-globule transition by different methods are also introduced for DNA in Chaps. 3 and 14. An elongational flow field provides information that cannot be obtained in experiments in a shear field. In Chap. 3, the history of investigation of flexible polymer molecules by the elongational flow birefringence and its application to various conformational transitions are reviewed. Studies on the interactions of DNA and DNA-binding proteins employing this technique are also introduced. In systems containing surfactants, even a variety of complex structures are formed. In Chap. 4, the shear-induced irreversible structure transformation in multilamellar systems consisting of nonionic surfactants, which is controlled by the intermolecular repulsion of added polymer molecules, is reviewed. A universal rheological picture induced by defects in multilamellar systems is proposed.

Although it is well known that the collective diffusion and the thermal diffusion are coupled to affect each other in accordance with Onsager’s reciprocal theorem, its application to biopolymer solutions has been achieved only recently in a newly developed methodology and apparatus. The Soret coefficient, which characterizes the coupling of two types of current determined from measurements, is a promising tool for microfluidic separation and thermophoresis in biomolecular solutions. In Chap. 5, recent developments in apparatus and experimental results for studying the thermal diffusion using laser holography are reviewed.

In Chaps. 6 and 7, recent progress in the biorheological application of nuclear magnetic resonance is introduced. The development of nucleic magnetic resonance has afforded many measurement modes. In pulsed gradient diffusion experiments called PGSE, the magnetization is excited with a 90° radiofrequency pulse and then dispersed, and a spin echo is the refocusing of spin magnetization by a pulse of resonant electromagnetic radiation. Using this method, the high mobility of water in biological systems can be observed. In Chap. 6, the diffusion of water in typical biological systems is reviewed. By taking an image of the wave intensity distribution in a tissue, induced externally using magnetic resonance imaging, magnetic resonance elastography (MRE) can be performed noninvasively. In Chap. 7, the theoretical basis of this technique is surveyed, the current state of medical applications is reviewed, and a physical and mathematical basis is given.

In Chaps. 8 and 9, recent topics related to the progress of dielectric spectroscopy are introduced. The improvement of electronic devices enables measurements to be performed with high precision and in situ broadband dielectric relaxation spectra to be obtained. In particular, the various states of water in biological systems can now be identified. In Chap. 8, the basis of this technique and the dynamics of water and biomacromolecules, along with their application in vivo to tissues such as skin, are described. Chapter 9 focuses on the glass transition of water in various biomaterials such as foods.