The fabrication of nanostructures in a bottom-up approach from specific molecular precursors offers the opportunity to create tailored materials for applications in nanoelectronics. However, the formation of defect-free two-dimensional (2D) covalent networks remains a challenge, which makes it difficult to unveil their electronic structure. Here we report on the hierarchical on-surface synthesis of nearly defect-free 2D covalent architectures with carbonyl-functionalized pores on Au(111), which is investigated by low-temperature scanning tunnelling microscopy in combination with density functional theory calculations. The carbonyl-bridged triphenylamine precursors form six-membered macrocycles and one-dimensional (1D) chains as intermediates in an Ullmann-type coupling reaction that are subsequently interlinked to 2D networks. The electronic band gap is narrowed when going from the monomer to 1D and 2D surface-confined π-conjugated organic polymers comprising the same building block. The significant drop of the electronic gap from the monomer to the polymer confirms an efficient conjugation along the triphenylamine units within the nanostructures.

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Wilson's disease presenting as acute liver failure (ALF) is potentially fatal, and liver transplantation (LTx) is the only option. We report two patients with Wdson's disease and ALF treated with the Molecular Adsorbents Recirculating System (MARS). Both patients fulfilled criteria for poor prognosis. Because LTx was not available immediately in either case, MARS was used as a bridge to LTx. In Case 1, serum bilirubin decreased from 803 to 425 pmol/L after 3 treatments, but increased to 656 pmol/L during a break, decreasing again to 457 pmol/L with further treatment. Serum copper decreased from 53.7 pmol/L, to 35.8 pmol/L after first treatment session, and 17.4 pmol/L at treatment completion. In Case 2, MARS treatment over 2 weeks reduced serum bilirubin from 1200 to 450 pmollL and copper from 35 to 13 pmol/L with marked improvement in encephalopathy and reduction in ammonia (59 to 34 pmol/L). Both patients were successfully bridged to LTx (days 9 and 28, respectively). Analysis of albumin-dialysate from the MARS circuit suggested that copper removal occurred mostly in the first few hours of treatment, partly being adsorbed by albumin and partly by the MARSFlux membrane (Teraklin AG, Rostock, Germany). These data suggest that M A R S removes copper efficiently and can be used to bridge patients with Wilson's disease and ALF to LTx. (Liver Transpl2002;8: 962-3671 W ilson's disease is an autosomal recessive hereditary disease of copper metabolism in which copper transport from the liver is impaired,' resulting in its accumulation in the liver. The commonest modes of presentation are either as a chronic liver disease, or as a neurologic dis0rder.~,3 Acute liver failure is one of the

Graphene grown on Rh(111) was used as a template for the growth of Pd nanoclusters. Using high-resolution synchrotron radiation-based X-ray photoelectron spectroscopy, we studied the deposition of Pd on corrugated graphene in situ. From the XP spectra, we deduce a cluster-by-cluster growth mode. The formation of clusters with 3 nm diameter was confirmed by low-temperature scanning tunneling microscopy measurements. The investigation of the thermal stability of the Pd particles showed three characteristic temperature regimes: Up to 550 K restructuring of the particles takes place, between 550 and 750 K the clusters coalesce into larger agglomerates, and finally between 750 and 900 K Pd intercalates between the graphene layer and the Rh surface.