Optimization of comb‐shaped polycarboxylate cement dispersants to achieve fast‐flowing mortar and concrete

Concretes and mortars possessing a low water‐to‐cement (w/c) ratio (<0.40) liquefied with comb‐shaped polycarboxylate (PCE) copolymers commonly exhibit a sticky, honey‐like consistency, and slow flow behavior. The stickiness is owed to high plastic viscosity of the suspension. In this study, different PCE comb polymers based on methacrylate ester, allyl, vinyl, and isoprenyl ether macromonomers were synthesized and analyzed. It was found that their hydrophilic–lipophilic balance (HLB) value, i.e., the balance between the hydrophilic and lipophilic parts in these PCE molecules determines their effect on the plastic viscosity of a concrete. PCE copolymers mainly composed of hydrophilic parts, i.e., such possessing high HLB values, impart low plastic viscosity. Allyl ether—maleic acid based PCEs exhibit especially high HLB values and thus impart low plastic viscosity. Higher viscosities were recorded for isoprenylether PCEs, while methacrylate‐ester and vinyl ether PCEs possess particularly low HLB values and hence produce a pronounced sticky concrete. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42529.     

The Importance of Caveolin-1 as Key-Regulator of Three-Dimensional Growth in Thyroid Cancer Cells Cultured under Real and Simulated Microgravity Conditions

We recently demonstrated that the CAV1 gene was down-regulated, when poorly differentiated thyroid FTC-133 cancer cells formed spheroids under simulated microgravity conditions. Here, we present evidence that the caveolin-1 protein is involved in the inhibition of spheroid formation, when confluent monolayers are exposed to microgravity. The evidence is based on proteins detected in cells and their supernatants of the recent spaceflight experiment: “NanoRacks-CellBox-Thyroid Cancer”. The culture supernatant had been collected in a special container adjacent to the flight hardware incubation chamber and stored at low temperature until it was analyzed by Multi-Analyte Profiling (MAP) technology, while the cells remaining in the incubation chamber were fixed by RNAlater and examined by mass spectrometry. The soluble proteins identified by MAP were investigated in regard to their mutual interactions and their influence on proteins, which were associated with the cells secreting the soluble proteins and had been identified in a preceding study. A Pathway Studio v.11 analysis of the soluble and cell-associated proteins together with protein kinase C alpha (PRKCA) suggests that caveolin-1 is involved, when plasminogen enriched in the extracellular space is not activated and the vascular cellular adhesion molecule (VCAM-1) mediated cell–cell adhesion is simultaneously strengthened and activated PRKCA is recruited in caveolae, while the thyroid cancer cells do not form spheroids.     

A Novel Coenzyme A Analogue in the Anaerobic,Sulfate-Reducing,Marine Bacterium Desulfobacula toluolica Tol2T

Coenzyme A (CoA) thioesters are formed during anabolic and catabolic reactions in every organism. Degradation pathways of growth-supporting substrates in bacteria can be predicted by differential proteogenomic studies. Direct detection of proposed metabolites such as CoA thioesters by high-performance liquid chromatography coupled with high-resolution mass spectrometry can confirm the reaction sequence and demonstrate the activity of these degradation pathways. In the metabolomes of the anaerobic sulfate-reducing bacterium Desulfobacula toluolica Tol2^T grown with different substrates various CoA thioesters, derived from amino acid, fatty acid or alcohol metabolism, have been detected. Additionally, the cell extracts of this bacterium revealed a number of CoA analogues with molecular masses increased by 1 dalton. By comparing the chromatographic and mass spectrometric properties of synthetic reference standards with those of compounds detected in cell extracts of D. toluolica Tol2^T and by performing co-injection experiments, these analogues were identified as inosino-CoAs. These CoA thioesters contain inosine instead of adenosine as the nucleoside. To the best of our knowledge, this finding represents the first detection of naturally occurring inosino-CoA analogues.     

Dynamische Berechnung von Eisenbahnbrücken im Zuge von Hochgeschwindigkeitsstrecken – Ein alternatives Verfahren zur Simulation von Zugüberfahrten

Dynamic analysis of high speed railway bridges. The new EUROCODE‐based design code regulations require attention to Structural Dynamics. An alternative analysis method, easier to use and requiring less computer time than the usual time stepping procedure, is shown and applied for Dynamic Analysis of high speed railway bridges.     

Stereoselectivity of Four (R)‐Selective Transaminases for the Asymmetric Amination of Ketones

Four (R)‐ω‐transaminases originating from Hyphomonas neptunium (HN‐ωTA), Aspergillus terreus (AT‐ωTA) and Arthrobacter sp. (ArR‐ωTA), as well as an evolved transaminase (ArRmut11‐ωTA) were successfully employed for the amination of prochiral ketones leading to optically pure (R)‐amines. The first three transaminases displayed perfect stereoselectivity for the amination of all substrates tested (ee >99%). Furthermore, the transaminase AT‐ωTA led in most cases to better conversion than ArR‐ωTA and HN‐ωTA using D ‐alanine as amine donor. α‐Tetralone, which was the only substrate not accepted by HN‐ωTA, ArR‐ωTA, and AT‐ωTA, was successfully transformed with perfect enantioselectivity (ee >99%) into the corresponding optically pure amine employing the variant ArRmut11‐ωTA.