Highly transparent Bi2MoO6- and Bi2WO6-polymer nanocomposites.

A combined method of precipitation, phase transfer into organic solvent, solvothermal treatment and subsequent in situ polymerization was used to integrate nanocrystalline Bi2MoO6- and Bi2WO6-particles into a polymer matrix of poly-laurylacrylate. The presented method offers a new and gentle way to produce highly transparent bulk nanocomposites containing evenly distributed Bi2MoO6- and Bi2WO6-nanoparticles. Characterization results of DLS-, XRD-, REM- and TEM-measurements are presented as well as solid state UV/VIS-measurements of the particles. The transparent nanocomposites were characterized using UV/VIS-spectroscopy and ellipsometry. All composites show a good transmission in the range from 800-400 nm. The particle content of the nanocomposites was measured with TG-measurements.

A role for Ctr9p and Paf1p in the regulation G1 cyclin expression in yeast.

Entry into the cell cycle in budding yeast involves transcriptional activation of G1cyclin genes and DNA synthesis genes when cells reach a critical size in late G1. Expression of G1cyclins CLN1 and CLN2 is regulated by the transcription factor SBF (composed of Swi4p and Swi6p) and depends on the cyclin-dependent Cdc28 protein kinase and cyclin Cln3p. To identify novel regulators of SBF-dependent gene expression we screened for mutants that fail to activate transcription of G1cyclins. We found mutations in a gene called CTR9. ctr9 mutants are inviable at 37 degrees C and accumulate large cells. CTR9 is identical to CDP1. CTR9 encodes a conserved nuclear protein of 125 kDa containing several TPR repeats implicated in protein-protein interactions. We show that Ctr9p is a component of a high molecular weight protein complex. Using immuno-affinity chromatography we found that Ctr9p associates with polypeptides of 50 and 65 kDa. By mass spectrometry these were identified as Cdc73p and Paf1p. We show that Paf1p, like Ctr9p, is required for efficient CLN2 transcription, whereas Cdc73p is not. Paf1p and Cdc73p were previously reported to be RNA poly-merase II-associated proteins, suggesting that the Ctr9p complex may interact with the general transcription apparatus.