Although urban quality of life is one of the important topics in most of the European policies, these policies are not supported by empirical analysis. Furthermore, there are few studies in urban quality of life area that consider a sufficiently large number of cities and related factors and those that focused on European cities applied parametric analysis techniques that cannot handle multicollinearity. To remedy the aforementioned shortcomings, in this study, a large number of factors related to urban quality of life are investigated in different European cities, and to handle multicollinearity, non-parametric analysis techniques are adopted. The data stem from the Eurostat (2015), collecting information on urban quality of life for > 40,000 citizens in 112 urban areas. Different non-parametric modeling techniques are applied and the results of the method that yielded the highest overall accuracy, i.e. the C5.0 algorithm, are presented. The results show that from the wide scope of considered factors, five main variables play an important role in urban life satisfaction, i.e. (i) feeling safe in the city, (ii) satisfaction with healthcare services in the city, (iii) satisfaction with the state of streets and buildings in the neighborhood, (iv) satisfaction with public transport in the city, and (v) availability of retail shops.

The complement system has developed different strategies to clear infections by several effector mechanisms, such as opsonization, which supports phagocytosis, attracting immune cells by C3 and C5 cleavage products, or direct killing of pathogens by the formation of the membrane attack complex (MAC). As the Zika virus (ZIKV) activates the classical complement pathway and thus has to avoid clearance by the complement system, we analyzed putative viral escape mechanisms, which limit virolysis. We identified binding of the recombinant viral envelope E protein to components of the terminal pathway complement (C5b6, C7, C8, and C9) by ELISA. Western blot analyses revealed that ZIKV E protein interfered with the polymerization of C9, induced on cellular surfaces, either by purified terminal complement proteins or by normal human serum (NHS) as a source of the complement. Further, the hemolytic activity of NHS was significantly reduced in the presence of the recombinant E protein or entire viral particles. This data indicates that ZIKV reduces MAC formation and complement-mediated lysis by binding terminal complement proteins to the viral E protein.