A B S T R A C TThe potential and adaptive flexibility of population dynamic P-systems (PDP) to study population dynamics suggests that they may be suitable for modelling complex fluvial ecosystems, characterized by a composition of dynamic habitats with many variables that interact simultaneously. Using as a model a reservoir occupied by the zebra mussel Dreissena polymorpha, we designed a computational model based on P systems to study the population dynamics of larvae, in order to evaluate management actions to control or eradicate this invasive species. The population dynamics of this species was simulated under different scenarios ranging from the absence of water flow change to a weekly variation with different flow rates, to the actual hydrodynamic situation of an intermediate flow rate. Our results show that PDP models can be very useful tools to model complex, partially desynchronized, processes that work in parallel. This allows the study of complex hydroecological processes such as the one presented, where reproductive cycles, temperature and water dynamics are involved in the desynchronization of the population dynamics both, within areas and among them.The results obtained may be useful in the management of other reservoirs with similar hydrodynamic situations in which the presence of this invasive species has been documented.2014 Published by Elsevier B.V.

In the present work, several mechanisms of four bars for knee prosthesis were studied and evaluated. We compared and defined the design parameters as well as an optimization method in terms of their stability and voluntary control to get a new mechanism. Few methods have been published to compare the performance and design parameters of the wide variety of polycentric knee mechanisms. In this work, we developed a method for performance comparison of polycentric knee mechanisms and designing a stable and novel four-bar mechanism with a voluntary control configuration. We defined design parameters for the optimization of a stable knee mechanism with voluntary control, presented a new dimensional design that can be functional for transfemoral users with different anthropometric characteristics and contributed with a simple method to obtain a mechanism with optimal sizing. A comparison of dimensional parameters of several mechanisms of knee prosthesis was obtained. There is the proposal of a new optimized mechanical configuration for assuring the voluntary control and a stable trajectory of the knee mechanism. With this method, it is possible to compare and design personalized mechanisms. Clinical relevance This method proposes a simple way to evaluate polycentric knees, and it is easy to use to compare and design stable mechanisms with voluntary control for transfemoral users with personal design parameters, if required.

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A variety of technologies is available for the decontamination and dismantling of nuclear facilities. All over the world, these technologies as well as conditioning processes of decommissioning waste are further developed. So far, they have been mainly applied to the dismantling of research and prototype facilities. Dismantling of reactors of higher power has started with the nuclear power plants of Greifswald and Würgassen among others. The present paper shall present the state of the art of decontamination and dismantling techniques as well as of post-treatment processes of radioactive decommissioning waste. From the technical point of view, the most complex step is the remote dismantling of activated and highly contaminated components. The prototype facilities of Forschungszentrum Karlsruhe, which are currently being dismantled, cover all types of plants. Their status of dismantling and the experience gained from using decommissioning technologies that are also suited for power facilities shall be illustrated. Further developments and adaptations of individual techniques, e. g. thermal and mechanical cutting methods, as well as of the complete systems technology, including carrier system, manipulator system, and tools, are reasonable and indispensable for managing the variety of dismantling tasks and, not least, for reducing their operation times and costs of use.