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There have been a large number of systems that integrate logic and objects (frames or classes) for knowledge representation and reasoning. Most of those systems give pre-eminence to logic and their objects lack the structure of frames. These choices imply a number of disadvantages, as the inability to represent exceptions and perform default reasoning, and the reduction in the naturalness of representation. In this paper, aspects of knowledge representation and reasoning in SILO, a system integrating logic in objects, are presented. SILO gives pre-eminence to objects. A SILO object comprises elements from both frames and classes. A kind of many-sorted logic is used to express object internal knowledge. Message passing, alongside inheritance, plays a significant role in the reasoning process. Control knowledge, concerning both deduction and inheritance. is separately and explicitly represented via definitions of certain functions, called meta-functions.

In order to move towards a sustainable existence in our critically energy dependent society there is a continuing need to adopt environmentally sustainable methods for energy production, storage and conversion. A fuel cell is an energy conversion device that generates electricity and heat by electrochemically combining a gaseous fuel and an oxidant gas through electrodes and across an ion conducting electrolyte. The use of fuel cells in both stationary and mobile power applications can offer significant advantages for the sustainable conversion of energy. Currently the cost of fuel cell systems is greater than that of similar, already available products, mainly because of small scale production and the lack of economies of scale. The best fuel for fuel cells is hydrogen and another barrier is fuel flexibility. Benefits arising from the use of fuel cells include efficiency and reliability, as well as economy, unique operating characteristics and planning flexibility and future development potential. By integrating the application of fuel cells, in series with renewable energy storage and production methods, sustainable energy requirements may be realized. As fuel cell application increases and improved fuel storage methods and handlings are developed, it is expected that the costs associated with fuel cell systems will fall dramatically in the future.

Several results on Q_p spaces and their meromorphic counterparts, classes, are mentioned. We study the properties of an important function which show that there are some curious differences between the spaces of analytic functions and their corresponding classes of meromorphic functions in the unit disk.