Fully consistent X-ray data and molecular dynamics simulations on new star-shaped liquid crystals yield two nanosegregated architectures with a coaxial stacking of two functional discotic units: tris(triazolyl)triazine and triphenylene. Analysis of lattice order along the principal axes reveals preferential staggered arrangement of the stacked molecules in the columnar assembly.

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Understanding the forces governing human behavior and social dynamics is a challenging problem. Individuals' decisions and actions are affected by interlaced factors, such as physical location, homophily, and social ties. In this paper, we propose to examine the role that distinct communities, linked to these factors, play as sources of social influence. The ego network is typically used in the social influence analysis. Our hypothesis is that individuals are embedded in communities not only related to their direct social relationships, but that involve different and complex forces. We analyze physical, homophily, and social communities to evaluate their relation with subjects' behavior. We prove that social influence is correlated with these communities, and each one of them is (differently) significant for individuals. We define community-based features, which reflect the subject involvement in these groups, and we use them with a supervised learning algorithm to predict subject participation in social events. Results indicate that both communities and ego network are relevant sources of social influence, confirming that the ego network alone is not sufficient to explain this phenomenon. Moreover, we classify users according to the degree of social influence they experienced with respect to their groups, recognizing classes of behavioral phenotypes. To our knowledge, this is the first work that proves the existence of phenotypes related to the social influence phenomenon.

The mathematical model of urban dynamics introduced in an earlier paper is applied to a case study in a small region in the southern part of Switzerland. The model mixes the point of view of cellular automata (cellular decomposition of the space, neighbourhood relations among cells, dynamics based on local evolution rules) with the approach to multiagent systems: the dynamics of the urban system are described in terms of decision processes of agents formalized using fuzzy-decision-theory methods. The region chosen for the case study evolves under the pressure of the nearby city of Lugano, owing to several factors: the accessibility of the area from Lugano, the availability of spatial resources for new development, the high level of quality of space, and the high level of congestion of Lugano. Local changes in the master plan from agricultural to residential use are taken into account, by introducing suitable memory variables that keep track of the demand of spatial resources for building in the recent past. Computer simulations showing the time evolution of the spatial distribution of the population and the real estate value are presented. The use of measures of attractiveness based on a fuzzy logic approach, and of Poisson-distributed events, enables us to introduce new effective approaches to parameter calibration and model validation.