Alexander Steiner

Learn More
Plant cytokinesis is initiated in a transient membrane compartment, the cell plate, and completed by a process of maturation during which the cell plate becomes a cross wall. How the transition from juvenile to adult stages occurs is poorly understood. In this study, we monitor the Arabidopsis transport protein particle II (TRAPPII) and exocyst tethering(More)
OBJECTIVES In dental implant surgery, computer-aided surgery (CAS) techniques can provide a high medical benefit. Two different techniques are established for transferring a CAS treatment planning to the patient: the use of surgical templates (splints) or intraoperative navigation using optical tracking. The aim of this study was to evaluate the total(More)
Nanoporous molecular frameworks are important in applications such as separation, storage and catalysis. Empirical rules exist for their assembly but it is still challenging to place and segregate functionality in three-dimensional porous solids in a predictable way. Indeed, recent studies of mixed crystalline frameworks suggest a preference for the(More)
All the intermediates in the "carboalkoxy" pathway, and their interconversions giving complete catalytic cycles, for palladium-diphosphine-catalyzed hydroalkoxycarbonylation of alkenes, and for alkene-CO copolymerization, have been demonstrated using (31)P{(1)H} and (13)C{(1)H} NMR spectroscopy. The propagation and termination steps of the "hydride" cycles(More)
Microtubule-associated protein-2 (MAP-2) is a prominent cytoskeletal protein in the mammalian nervous system. Two high-molecular-weight (HMW) MAP-2 isoforms, MAP-2a and MAP-2b, are developmentally regulated. MAP-2b is expressed through the life of the neuron, while MAP-2a expression coincides with the time of synaptic formation. MAP-2a and MAP-2b differ in(More)
Porous materials are important in a wide range of applications including molecular separations and catalysis. We demonstrate that covalently bonded organic cages can assemble into crystalline microporous materials. The porosity is prefabricated and intrinsic to the molecular cage structure, as opposed to being formed by non-covalent self-assembly of(More)
The selective uptake of guests in molecular-sized channels underpins function in biological membranes and in materials for molecular separations. Synthetic porous networks can respond structurally towards guest sorption suggesting applications, for example, as enzymemimics. We report here an organic cage molecule where the porosity can be switched on and(More)
Interlocked molecules comprise two or more separate components that are joined by 'mechanical' rather than covalent bonds. In other words, these molecular assemblies cannot be dissociated without the cleavage of one or more chemical bonds. Although recent progress has enabled the preparation of such topologies through coordination or templating(More)
Cyclotriphosphazenes have been functionalized with various oxo-groups at one of the ring phosphorus atoms. Starting from geminal dichlorides (A) which are equipped with amino groups at the other two phosphorus atoms {(Z'(2)P)(2)N(3)PCl(2) (Z' = NHCy) and (Z''P)(2)N(3)PCl(2) (Z'' = {EtN(C(3)H(6))NEt}), respectively}, phosphate (B), pyrophosphate (C),(More)
Cytokinesis, the partitioning of the cytoplasm following nuclear division, requires extensive coordination between membrane trafficking and cytoskeletal dynamics. In plants, the onset of cytokinesis is characterized by the assembly of a bipolar microtubule array, the phragmoplast, and of a transient membrane compartment, the cell plate. Little is known(More)