Waste from brewing (trub) as a source of protein for the food industry

The use of agro-industrial waste for food enrichment can be limited, due to taste, odour, colour and other unpleasant characteristics. Trub (brewing waste) has important nutrients, such as proteins and carbohydrates, and phytochemical compounds; however, its applications are hindered by the astringent flavour. In order to reduce the bitterness of trub, aqueous extractions were realized at high temperature (100 °C per 1 h) in five steps. Two fractions were obtained; a liquid fraction (containing bitter compounds) and a solid fraction (the trub after the extraction process; TAP). Both fractions and the trub before the extraction process (TBP) were evaluated. The bitterness of TBP was significantly reduced in TAP while the protein content increased; TAP presented a branched network and changes in its structure. The reduction in bitterness and the high protein content allows the use of trub in the food industry.     

Effect of sintering duration on the sliding-wear resistance of 3Y-TZP dental ceramics

Zirconia doped with 3 mol% yttria (3Y-TZP) is widely employed in prosthetic dentistry. The standard routine in the manufacture of prostheses involves subtractive machining of a commercial presintered block, followed by pressureless sintering up to full densification using one of the heat treatments indicated by the supplier, so as to obtain adequate strength. Usually, however, little information is provided on how these treatments affect the wear resistance. The present work therefore investigated how three sintering cycles of different durations recommended by a commercial supplier affected the microstructure and long-term degradation in the form of sliding-wear of the resulting 3Y-TZP ceramics. It was found that the three cycles essentially resulted in the same wear behavior (ie, wear modes and mechanisms, as well as specific wear rate ~5·10^–6 mm³/Nm). The results are analyzed within the framework of existing abrasive wear models, and implications for the manufacture of durable prostheses are discussed.     

Modelling, simulation and control of an industrial, semi-batch, emulsion-polymerization reactor

This paper presents an emulsion-polymerization model that is designed for an industrial, semi-batch reactor. The model consists of a reaction model and a calorimetry model, and as such enables us to predict the reactor temperature and the batch-output parameters, i.e., the conversion, the solids content and the viscosity. The model was validated on real-plant data and used in the analysis and design of the reactants dosing control. The control strategy proposed is valid for cases where evaporative cooling is either the only or an additional way to remove the heat of the reaction. It consists of an initiator and monomer dosing control, using the reactor temperature as a controlled variable. The simulation results and the real-plant testing show that the proposed reactants dosing control significantly reduces the variations in the reactor temperature and at the same time results in more uniform batch results.     

Suggesting model transformation repairs for rule-based languages using a contract-based testing approach

Software and Systems Modeling - Model transformations play an essential role in most model-driven software projects. As the size and complexity of model transformations increase, their reuse,...     

A Temperature-Driven,Reversible, Helical-Handedness Inversion in Peptaibol Analogues Tuned by the C-Terminal Capping Moiety

Trichogin is a natural peptide endowed with antimicrobial and antitumor activity. A member of the peptaibol family, trichogin possesses a C-terminal amino alcohol. In the past, this moiety was substituted for a methyl ester for synthetic purposes and it was observed that this apparently slight modification caused significant changes in the peptide bioactivity. With the aim of understanding the reasons behind such observations, a detailed spectroscopic study on a number of trichogin analogues has been performed. Herein, data obtained from synchrotron radiation circular dichroism, NMR spectroscopy, and fluorescence spectroscopy in organic solvents at cryogenic temperatures are compared with those independently acquired by means of EPR spectroscopy at 80 K. It is unambiguously revealed that the presence of a reversible, temperature-driven, screw-sense interconversion from a right- to left-handed helix is determined by the C-terminal capping moiety. Data demonstrate, for the first time, the key role of a C-terminal methyl ester in promoting peptide screw-sense inversion.     

All-carbon N-heterocyclic Carbene-catalyzed (3+2) Annulation using Donor-Acceptor Cyclopropanes

Donor-acceptor cyclopropanes are known to serve as dipole precursors capable of engaging in (3+2) annulations with electron-deficient π-systems. In 2013, the reaction of donor-acceptor cyclopropanes with α,β-unsaturated acyl fluorides in an all-carbon (3+2) annulation was discovered. The reaction proceeds in good yields using the IMes NHC to provide diastereomerically pure β-lactone-fused cyclopentanes bearing four contiguous stereocentres. Subsequent studies demonstrated that N-t-butyl substituted homochiral morpholinone NHCs allowed the reaction to be achieved in up to 98 % ee. In this account, a background to this reaction is introduced, along with a complete account of the strengths, limitations and challenges encountered while developing this chemistry.