In an aging society it is extremely important to develop devices, which can support and aid the elderly in their daily life. This demands means and tools that extend independent living and promote improved health. Thus, the goal of this article is to review the state of the art in the robotic technology for mobility assistive devices for people with mobility disabilities. The important role that robotics can play in mobility assistive devices is presented, as well as the identification and survey of mobility assistive devices subsystems with a particular focus on the walkers technology. The advances in the walkers' field have been enormous and have shown a great potential on helping people with mobility disabilities. Thus it is presented a review of the available literature of walkers and are discussed major advances that have been made and limitations to be overcome.

The prefrontal cortex (PFC) has been implicated in the ability to apply semantic organizational strategies during verbal encoding and episodic learning. However, there has been no direct evidence demonstrating which specific areas in the PFC are engaged after cognitive training using semantic organizational strategies in healthy adult human subjects. In this study, we investigated the effects of semantic strategic training on brain activity and changes in behavioral performance, after cognitive training, using functional MRI (fMRI). There was a significant activation in bilateral dorsolateral prefrontal (DLPF) and orbitofrontal (OFC) areas after cognitive training. These results demonstrate the engagement of bilateral DLPF and OFC cortex during strategic memory processes, particularly when mobilization and effort of effective use of strategies are required. The functional adaptations observed here may also shed light on some of the processes underlying recovery with cognitive rehabilitation in patient populations with brain injury.

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I compared the effectiveness of sympatric brown howlers (Alouatta guariba) and muriquis (Brachyteles arachnoides) as seed dispersers in terms of quantitative and qualitative attributes. I hypothesized that differences in feeding and behavioral patterns between these large‐bodied folivorous/frugivorous primates would lead to dissimilarities in their effectiveness as endozoochoric seed dispersal agents. The study was carried out in a semideciduous forest fragment of Fazenda Barreiro Rico, southeastern Brazil. Through behavioral sampling of frugivory and defecation events as well as analyses of fecal samples, I determined that A. guariba dispersed fewer species and produced a lower proportion of dung with intact seeds than B. arachnoides. There was no difference between the number of seeds in fecal samples of A. guariba and B. arachnoides. These primates affected to a similar degree both germination percentage and latency to germination of seeds they ingested or removed the pulp from. Howlers and muriquis were also similar in carrying seeds away from the parent trees. Contrary to muriquis, howlers defecated seeds under the canopy of conspecific lianas, where seeds are expected to suffer high mortality rates, and voided seeds predominantly in a clumped pattern. B. arachnoides was a more effective seed disperser when compared to A. guariba in some attributes evaluated, but not in others. Given the interspecific variation in recruitment patterns of tropical plants and the loss of frugivorous bird species at the study site, the differences between howlers and muriquis in their abilities as seed dispersers may crucially influence the composition and maintenance of seedling diversity.