The underlying modules of existentially closed ▵-algebras are studied. Among other things, it is proved that they are all elementarily equivalent, and that all of them are existentially closed as modules if and only if ▵ is regular. It is also proved that every saturated module in the appropriate elementary equivalence class underlies an e.c. ▵-algebra. Applications to some problems in module theory are given. A number of open questions are mentioned.

Of the large industrial countries, Germany is clearly leading with regard to new renewable energy sources, occupying first rank in terms of installed capacity for wind energy and second for photovoltaics. This is not because of an exceptional natural resource base but because of public policy in this area, despite the fact that this policy was conducted in a lukewarm fashion until 1998. In any case, it led to a remarkable expansion of this sector. The Red-Green coalition, in office from (...) 1998 to 2005, developed the vision of achieving 50% and more of electricity generated from renewable energy sources by 2050, a goal that seems well accepted by the public but not by the established energy interests. There seems to be a good chance that the Conservative-Social Democratic coalition, which took office in November 2005, will continue this course. (shrink)