Highlights Data-informed methodology calculates the level of traffic stress of cyclists. Method scales to massive data sets by coupling a classifier with a predictive model. Methodology tested on the road network of Bogotá (Colombia) Web-enabled dashboard supports policy making and interventions to reduce stress. Number of bicyclists’ collisions per kilometer correlates with higher stress.

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The advantages of the increasing usage of mobile devices that operate under the multihoming scheme are changing the communications world drastically. Therefore, next generation networks operators have the challenging task to distribute connections of mobile devices efficiently over their access networks, creating a big heterogeneous wireless network for telecommunications. We present a mixed integerlinear programming (MILP) model to balance the load of multiple services over wireless networks taking into account three key indicators: connection loads of access networks, connection costs, and battery consumption of connections. To solve the multi-objective problem, we propose a multi-objective Tabu Search procedure that is capable to find non-supported solutions in the online efficient set. To test the performance of our multi-objective Tabu Search, we tested it over four instances of the literature. In the first instance, a small instance, our procedure finds the true efficient set of solutions. For the other three instances, large instances with over a thousand mobile devices, our procedure finds good online efficient sets of solutions in less than 30 seconds. Finally, using appropriate multi-objective metrics, we compare the results of our multi-objective Tabu Search against the results of a state of the art multi-objective genetic algorithm in the literature for the same problem, outperforming the genetic algorithm in every instance tested.

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When cats are subjected to an atmosphere of 100 percent oxygen at a sufficiently low pressure, their sleeping patterns are changed: paradoxical sleep disappears and drowsiness increases. This change appears when the pressure decreases to a level close to that at which the hemoglobin begins to dissociate. Return of a cat to a normal atmosphere produces a rebound: the cat spends more time in paradoxical sleep than it did during the base-line period. This finding suggests that a mechanism, closely related to the metabolism of oxygen in the brain, must play an important role in the production of paradoxical sleep. Yet the increase in paradoxical sleep after decompression indicates that still other mechanisms must merge to produce paradoxical sleep.