Die organischen Verbindungen und Komplexe von Germanium,Zinn und Blei

This field is of special interest within the organometallic chemistry, which was and still is one of the most developing areas of chemistry for twenty years. The electronic structure around the atoms of germanium, tin, and lead favors both polar and radical reactions, and a plentiful coordination chemistry, too. Modern quantum chemistry arrived at these heavy atoms and allows better understanding also of low valent species, R₂M. Chiral compounds with asymmetric Sn atoms, an object aimed at since 1905, have been prepared now, and dynamic stereochemistry has been studied. Industrial use of organotins has grown quickly and includes stabilization of plastics and plant and material protection as well. Biomethylation and environmental problems open this field both to biochemists and ecologists.     

Corporate Responsibility: The Stakeholder Paradox Reconsidered

Is it legitimate for a business to concentrate on profits under respect for the law and ethical custom? On the one hand, there seems to be good reasons for claiming that a corporation has a duty to act for the benefit of all its stakeholders. On the other hand, this seems to dissolve the notion of a private business; but then again, a private business would appear to be exempted from ethical responsibility. This is what Kenneth Goodpaster has called the stakeholder paradox: either we have ethics without business or we have business without ethics. Through a different route, I reach the same solution to this paradox as Goodpaster, namely that a corporation is the instrument of the shareholders only, but that shareholders still have an obligation to act ethically responsibly. To this, I add discussion of Friedman’s claim that this responsibility consists in increasing profits. I show that most of his arguments fail. Only pragmatic considerations allow to a certain extent that some of the ethical responsibility is left over to democratic regulation.     

The Moral Foundation of the Precautionary Principle

The Commission's recentinterpretation of the Precautionary Principleis used as starting point for an analysis ofthe moral foundation of this principle. ThePrecautionary Principle is shown to have theethical status of an amendment to a liberalprinciple to the effect that a state only mayrestrict a person's actions in order to preventunacceptable harm to others. The amendmentallows for restrictions being justified even incases where there is no conclusive scientificevidence for the risk of harmful effects.However, the liberal tradition has seriousproblems in determining when a risk of harm isunacceptable. Nevertheless, reasonable liberalarguments in favor of precaution can be basedon considerations of irreversible harm andgeneral fear of harm. But it is unclear whenthere considerations can be overridden.Within the liberal framework, the Commissionadvocates a so-called proportional version ofthe Precautionary Principle. This should beclearly distinguished from a welfare-basedapproach to precaution based on risk-aversiveweighing up of expected costs and benefits.However, in the last resort, the Commissiondoes seem to make a covert appeal to suchconsiderations.     

Social encapsulation of beetle parasites by Cape honeybee colonies (Apis mellifera capensis Esch.)

Worker honeybees (Apis mellifera capensis) encapsulate the small hive beetle (Aethina tumida), a nest parasite, in propolis (tree resin collected by the bees). The encapsulation process lasts 1-4 days and the bees have a sophisticated guarding strategy for limiting the escape of beetles during encapsulation. Some encapsulated beetles died (4.9%) and a few escaped (1.6%). Encapsulation has probably evolved because the small hive beetle cannot easily be killed by the bees due to its hard exoskeleton and defensive behaviour.