**About the Editor**

#### **Viorel-Puiu Paun**

Viorel-Puiu Paun is full university professor of Physics at Politehnica University of Bucharest, Faculty of Applied Sciences, Physics Department, and corresponding member of Academy of Romanian Scientists. The main areas of his scientific interest are the nonlinear dynamics and chaos theory, with their applications in different physico-chemical systems (nanostructures, composites), biological systems, and in human organs, such as the brain, lungs, and stomach. More precisely, he is expert in fractal interpretation of common diagnostic medical imaging tests (X-rays, CT Scan, MRI, etc.). He is further preoccupied about the knowledge and use of new composite materials, successfully used in oral rehabilitation. He is interested in material physico-chemical properties, compatibility with human tissue and their validity over time, in operation. He has extensive research competences in all the above-mentioned fields, including the time series method, fractals analysis, and diffusion process. Viorel-Puiu Paun has published more than 150 papers in national and international journals, 115 ISI journal papers, 50 communications in national and international meetings (more than 30 on invitation), 577 citations without self-citations, respectively, and 20 books, chapters in books, and monographs. His Hirsch factor value is currently 22. He was a guest/visiting professor at nine prestigious universities in Europe, including among other University of Cambridge, UK (2015), Ecole Polytechnique F ´ ed´ erale de Lausanne (EPFL), Switzerland (1996–1997, ´ 2014), University of Florence, Italy (2011), ENSICA Toulouse, France (2007), School of Physical Sciences, Kent University, Canterbury, UK (2004, 2006).
