Predicting the influence of a p2-symmetric substrate on molecular self-organization with an interaction-site model

An interaction-site model can a priori predict molecular self-organisation on a new substrate in Monte Carlo simulations. This is experimentally confirmed with scanning tunnelling microscopy on Fréchet dendrons of a pentacontane template. Local and global ordering motifs, inclusion molecules and a rotated unit cell are correctly predicted.     

Charge as you like! Efficient manipulation of negative ion net charge in electrospray ionization of proteins and nucleic acids

Acidic proteins and nucleic acids such as RNA are most readily ionized in electrospray ionization (ESI) operated in negative-ion mode. The multiply deprotonated protein or RNA ions can be used as precursors in top- down mass spectrometry. Because the performance of the dissociation method used critically depends on precursor ion negative net charge, it is important that the extent of charging in ESI can be manipulated efficiently. We show here that (M - nH)(n-) ion net charge of proteins and RNA can be controlled efficiently by the addition of organic bases to the electrosprayed solution. Our study also highlights the fact that ion formation in ESI in negative mode is only poorly understood.     

Lifting maps from a vector space of Jacobi cusp forms to a subspace of elliptic modular forms

In this paper we construct a lifting map from a vector space of generalized Jacobi cusp forms to a certain subspace of elliptic cusp forms and vice versa such that both mappings are adjoint with respect to the Petersson scalar products.     

Trace analysis and speciation of copper by application of an urease reactor

Summary A method for metal speciation using an enzyme reactor is described. The enzyme urease is immobilized on a polymer support. The parameters of the inhibition procedure are investigated for the determination of copper in drinking and surface water samples. The results are compared with those obtained by atomic absorption spectrometry. It has been found that the enzyme urease was inhibited only by free copper ions.Dedicated to Professor Dr. Wilhelm Fresenius on the occasion of his 80th birthday