Korruption und globale öffentliche Güter

Corruption control is an important input into the production of public goods at the national and at the global level, including sound economic management, well-functioning markets, and reliable human security. Eventually corruption control is itself a public good, because its benefits are largely nonrival and nonexcludable. As the case study of Transparency International shows, civil society has emerged as an effective partner of government and private actors in generating information about the deleterious effects of corruption, raising public awareness, and placing the issue of corruption firmly on domestic and international agendas

Chance and Necessity in Evolution: Lessons from RNA

The relationship between sequences and secondary structures or shapes in RNA exhibits robust statistical properties summarized by three notions: (1) the notion of a typical shape (that among all sequences of fixed length certain shapes are realized much more frequently than others), (2) the notion of shape space covering (that all typical shapes are realized in a small neighborhood of any random sequence), and (3) the notion of a neutral network (that sequences folding into the same typical shape form networks that percolate through sequence space). Neutral networks loosen the requirements on the mutation rate for selection to remain effective. The original (genotypic) error threshold has to be reformulated in terms of a phenotypic error threshold. With regard to adaptation, neutrality has two seemingly contradictory effects: It acts as a buffer against mutations ensuring that a phenotype is preserved. Yet it is deeply enabling, because it permits evolutionary change to occur by allowing the sequence context to vary silently until a single point mutation can become phenotypically consequential. Neutrality also influences predictability of adaptive trajectories in seemingly contradictory ways. On the one hand it increases the uncertainty of their genotypic trace. At the same time neutrality structures the access from one shape to another, thereby inducing a topology among RNA shapes which permits a distinction between continuous and discontinuous shape transformations. To the extent that adaptive trajectories must undergo such transformations, their phenotypic trace becomes more predictable.Comment: 37 pages, 14 figures; 1998 CNLS conference; high quality figures at http://www.santafe.edu/~walte

Donor Substituted Sulfonyl Carbenes, 2: Organothio Sulfonyl Carbenes

Organothio sulfonyl carbenes 3 have been generated via ylid thermolysis or via a-elimination starting from a-chloro a-organothio sulfones and their derivatives. They have been captured by suitable nucleophilic trapping reagents (diazomethane, enol ethers, and others). Their nucleophilic carbenoid precursors could be trapped by an electrophilic olefin (ketene dithioacetal S,S-dioxides as Michael acceptors). Stable carbene Z-dimers could be obtained under various conditions. Bromine catalyzed isomerization to E-isomers proved to be reversible

Diagnostics: Indicators and Transparency in the Anti-Corruption Industry

Discussion of transparency and indexes of corruption and their effect on the growing anti-corruption movement. Trust in numbers may lead to opacity rather than transparenc

Less Can Be More: RNA-Adapters May Enhance Coding Capacity of Replicators

It is still not clear how prebiotic replicators evolved towards the complexity found in present day organisms. Within the most realistic scenario for prebiotic evolution, known as the RNA world hypothesis, such complexity has arisen from replicators consisting solely of RNA. Within contemporary life, remarkably many RNAs are involved in modifying other RNAs. In hindsight, such RNA-RNA modification might have helped in alleviating the limits of complexity posed by the information threshold for RNA-only replicators. Here we study the possible role of such self-modification in early evolution, by modeling the evolution of protocells as evolving replicators, which have the opportunity to incorporate these mechanisms as a molecular tool. Evolution is studied towards a set of 25 arbitrary ‘functional’ structures, while avoiding all other (misfolded) structures, which are considered to be toxic and increase the death-rate of a protocell. The modeled protocells contain a genotype of different RNA-sequences while their phenotype is the ensemble of secondary structures they can potentially produce from these RNA-sequences. One of the secondary structures explicitly codes for a simple sequence-modification tool. This ‘RNA-adapter’ can block certain positions on other RNA-sequences through antisense base-pairing. The altered sequence can produce an alternative secondary structure, which may or may not be functional. We show that the modifying potential of interacting RNA-sequences enables these protocells to evolve high fitness under high mutation rates. Moreover, our model shows that because of toxicity of misfolded molecules, redundant coding impedes the evolution of self-modification machinery, in effect restraining the evolvability of coding structures. Hence, high mutation rates can actually promote the evolution of complex coding structures by reducing redundant coding. Protocells can successfully use RNA-adapters to modify their genotype-phenotype mapping in order to enhance the coding capacity of their genome and fit more information on smaller sized genomes