59 research outputs found
Pilot Experiments with Electrodialysis and Ozonation for the Production of a Fertilizer from Urine
Pilot tests were performed with a process combination of electrodialysis and ozonation for the removal of micropollutants and the concentration of nutrients in urine. In continuous and batch experiments, maximum concentration factors up to 3.5 and 4.1 were obtained, respectively. The desalination capacity did not decrease significantly during continuous operation periods of several weeks. Membrane cleaning after 195 days resulted in approximately 35% increase in desalination rate. The Yeast Estrogen Screen (YES), a bioassay that selectively detects oestrogenic compounds, confirmed that about 90% of the oestrogenic activity was removed by electrodialysis. HPLC analysis showed that ibuprofen was removed to a high extent, while other micropollutants were below the detection limit. In view of the fact that ibuprofen is among the most rapidly transported micropollutants in electrodialysis processes, this result indicates that electrodialysis provides an effective barrier for micropollutants. Standardised plant growth tests were performed in the field with the salt solution resulting from the treatment by electrodialysis and subsequent ozonation. The results show that the plant height is comparable to synthetic fertilisers, but the crop yield is slightly lower. The latter is probably caused by volatilisation losses during field application, which can be prevented by improved application technologies
Investigation of catalysis by bacterial RNase P via LNA and other modifications at the scissile phosphodiester
We analyzed cleavage of precursor tRNAs with an LNA, 2′-OCH3, 2′-H or 2′-F modification at the canonical (c0) site by bacterial RNase P. We infer that the major function of the 2′-substituent at nt −1 during substrate ground state binding is to accept an H-bond. Cleavage of the LNA substrate at the c0 site by Escherichia coli RNase P RNA demonstrated that the transition state for cleavage can in principle be achieved with a locked C3′ -endo ribose and without the H-bond donor function of the 2′-substituent. LNA and 2′-OCH3 suppressed processing at the major aberrant m−1 site; instead, the m+1 (nt +1/+2) site was utilized. For the LNA variant, parallel pathways leading to cleavage at the c0 and m+1 sites had different pH profiles, with a higher Mg2+ requirement for c0 versus m+1 cleavage. The strong catalytic defect for LNA and 2′-OCH3 supports a model where the extra methylene (LNA) or methyl group (2′-OCH3) causes a steric interference with a nearby bound catalytic Mg2+ during its recoordination on the way to the transition state for cleavage. The presence of the protein cofactor suppressed the ground state binding defects, but not the catalytic defects
Leveraging ligand affinity and properties: discovery of novel benzamide-type cereblon binders for the design of PROTACs
Immunomodulatory imide drugs (IMiDs) such as thalidomide, pomalidomide, and lenalidomide are the most common cereblon (CRBN) recruiters in proteolysis-targeting chimera (PROTAC) design. However, these CRBN ligands induce the degradation of IMiD neosubstrates and are inherently unstable, degrading hydrolytically under moderate conditions. In this work, we simultaneously optimized physiochemical properties, stability, on-target affinity, and off-target neosubstrate modulation features to develop novel nonphthalimide CRBN binders. These efforts led to the discovery of conformationally locked benzamide-type derivatives that replicate the interactions of the natural CRBN degron, exhibit enhanced chemical stability, and display a favorable selectivity profile in terms of neosubstrate recruitment. The utility of the most potent ligands was demonstrated by their transformation into potent degraders of BRD4 and HDAC6 that outperform previously described reference PROTACs. Together with their significantly decreased neomorphic ligase activity on IKZF1/3 and SALL4, these ligands provide opportunities for the design of highly selective and potent chemically inert proximity-inducing compounds
Determination of trapping parameters in poly(p-phenylenevinylene) light-emitting devices using thermally stimulated currents
On Yearbooks
This contribution addresses the role of national yearbooks of international law in the formation and maintenance of national academic communities (“imagined communities”, if you will), and their potential role in the education of aspiring international lawyers. It takes personal reflections as its starting point, and eventually suggests that such yearbooks are well worth cherishing—they fill a void in the academic industrial process, a void left by the predominance attached to research monographs and journal articles.Peer reviewe
Biozide in Gebäudefassaden - Ökotoxikologische Effekte, Auswaschung und Belastungsabschätzung für Gewässer
Selectively deposited Ru top electrode on Pb(Zr[sub 0.3]Ti[sub 0.7])O[sub 3] and Ru step coverage on TiN by digital chemical vapor deposition
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