Moody's Investors Service has lowered the outlook for the credit ratings of three of Europe's strongest economies: Luxembourg, the Netherlands and Germany. It's part of a busy day in Europe that has investors on-edge -- markets there are barely moving.

The credit rating agency Moody's slashed the ratings of 15 of the world's biggest financial institutions, including Citigroup and Bank of America here in the U.S. and Barclays and Credit Suisse in Europe.

Europe correspondent Stephen Beard discusses why the European markets remained pretty steady despite the credit downgrades of several European countries, and why we ought to worry about the Greek debt talks collapsing.part of the endodermal "half". This statement was further corroborated by arguments collected from the literature.Whereas neither the endoderm nor the ectoderm alone are initially able to differentiate beyond a certain point - so-called atypical ectodermal and endodermal differentiation respectively - their interaction product, the mesoderm, apparently contains the information needed for differentiation into the characteristic mesodermal structures. Influences emanating from the differentiating mesoderm then enable both the ectoderm and the endoderm to proceed further on their path of differentiation.The role of the blastocoelic cavity - a cavity with a negative morphogenetic function - in thespatial interaction between the two primary components of the egg was elucidated. In the light of the conclusions mentioned above the centrifugation experiments ofPASTEELS (1953, 1954) were reinterpreted, whileSCHULTZE'S "Umkehrexperiment" byPENNERS andSCHLEIP (1928),PENNERS