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Two industrial polycarboxylate superplasticizer samples have been selected to be used within the Priority Program 2005 of the German Research Foundation (DFG SPP 2005). The PCE polymers were characterized via Size Exclusion Chromatography (SEC) to determine their molar masses ( M w , M n ), the polydispersity index (PDI) and the conversion rate which indicates the incorporation of the macromonomer into the polymer. The anionic charge amount of the PCE samples was assessed via charge titration employing a cationic polymer. Furthermore, the cement dispersing properties of the PCE polymers were captured via 'mini slump' tests so as to assess their ability to fluidize CEM I 42.5 R and CEM III/A 42.5 N samples, respectively. Also, interaction between the PCEs and the surface of the cements was investigated via adsorption and zeta potential measurements of aqueous cement suspensions. The results shall be used for the ongoing research within the Priority Program.

Protein expression is a primary area of interest for routine histological diagnostics and tissue-based research projects, but the limitations of its post-mortem applicability remain largely unclear. On the other hand, tissue specimens obtained during autopsies can provide unique insight into advanced disease states, especially in cancer research. Therefore, we aimed to identify the maximum post-mortem interval (PMI) which is still suitable for characterizing protein expression patterns, to explore organ-specific differences in protein degradation, and to investigate whether certain proteins follow specific degradation kinetics. Therefore, the proteome of human tissue samples obtained during routine autopsies of deceased patients with accurate PMI (6, 12, 18, 24, 48, 72, 96 h) and without specific diseases that significantly affect tissue preservation, from lungs, kidneys and livers, was analyzed by liquid chromatography–tandem mass spectrometry (LC–MS/MS). For the kidney and liver, significant protein degradation became apparent at 48 h. For the lung, the proteome composition was rather static for up to 48 h and substantial protein degradation was detected only at 72 h suggesting that degradation kinetics appear to be organ specific. More detailed analyses suggested that proteins with similar post-mortem kinetics are not primarily shared in their biological functions. The overrepresentation of protein families with analogous structural motifs in the kidney indicates that structural features may be a common factor in determining similar postmortem stability. Our study demonstrates that a longer post-mortem period may have a significant impact on proteome composition, but sampling within 24 h may be appropriate, as degradation is within acceptable limits even in organs with faster autolysis.