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An extensive experimental campaign on Li recovery from relatively dilute LiCl solutions (i.e., Li+ similar to 4000 ppm) is presented to identify the best operating conditions for a Li2CO3 crystallization unit. Lithium is currently mainly produced via solar evaporation, purification, and precipitation from highly concentrated Li brines located in a few world areas. The process requires large surfaces and long times (18-24 months) to concentrate Li` up to 20,000 ppm. The present work investigates two separation routes to extract Li+ from synthetic solutions, mimicking those obtained from low-content Li+ sources through selective Li+ separation and further concentration steps: (i) addition of Na2CO3 solution and (ii) addition of NaOH solution + CO2 insufflation. A Li recovery up to 80% and purities up to 99% at 80 degrees C and with high-ionic strength solutions was achieved employing NaOH solution + CO2 insufflation and an ethanol washing step.

Das Simulationstool 100prosim dient zur Erstellung von Energieszenarien. Es wird in Lehrveranstaltungen auf Bachelor- und Masterniveau sowohl für Präsenzlehre als auch für digitale Lehre eingesetzt. Die Studierenden diskutieren die zukünftige Entwicklung verschiedener Lebensbereiche, in denen Energie eingesetzt wird. Darauf basierend wird mithilfe des Simulationstools der Energiebedarf der Zukunft ermittelt. Dieser soll zu 100 % aus erneuerbaren Energien erzeugt werden. Bei dem notwendigen Ausbau der Erneuerbaren kommt es zu Nutzungskonkurrenzen aufgrund der Flächenbedarfe. Es wird in moderierten Diskussionen ausgehandelt, wie viel Energie auf der einen Seite eingespart und wie viel auf der anderen Seite an Erzeugungskapazität ausgebaut werden kann. Die Evaluation mehrerer Lehrveranstaltungen legt nahe, dass die Erstellung von Energieszenarien das Verständ¬nis für das Gesamtsystem und die gesellschaftlichen Abwägungsprozesse steigert. Eine qualitative Auswertung von transkribierten Diskussionen zeigt auf, welche Einstellungen und Haltungen im Hinblick auf die Transformation des Energiesystems auftreten., Voneinander Lehren lernen; 4

The questions this study aims to answer is if people recover from work by engaging in creative activity during their leisure time and what are the processes that can explain this effect. With a daily diary design over one workweek and a weekend questions about people’s leisure time will be asked. After one general questionnaire during the week three daily questionnaires and during the weekend two daily questionnaires follow. In the afterwork questionnaire people will be asked for their affective well-being, how creative they had to be at work and the time pressure during work. In the bedtime questionnaire scales of affective well-being, need satisfaction, absorption, self-expression, recovery experiences with respect to their leisure activities. In the morning affective well-being, self-efficacy and sleep quality will be assessed.

The questions this study aims to answer is if people who are engaging in promotion and prevention-focused job crafting do experience different effects over the day regarding their energy depletion, basic need fulfillment and work engagement. With a daily diary design over one workweek questions about employees’ job crafting will be asked. After one general questionnaire during the week three daily questionnaires follow. In the questionnaire before the lunchbreak people will be asked for their job daily job crafting behavior and their energy depletion. In the questionnaire after the break the satisfaction of the basic needs during work will be asked. After work energy depletion and work engagement will be assessed.

Inclusion bodies (IBs) often emerge upon overexpression of recombinant proteins in E. coli. From IBs, refolding is necessary to generate the native protein that can be further purified to obtain pure and active biologicals. This work focusses on refolding as a significant process step during biopharmaceutical manufacturing with an industrial perspective. A theoretical and historical background on protein refolding gives the reader a starting point for further insights into industrial process development. Quality requirements on IBs as starting material for refolding are discussed and further economic and ecological aspects are considered with regards to buffer systems and refolding conditions. A process development roadmap shows the development of a refolding process starting from first exploratory screening rounds to scale-up and implementation in manufacturing plant. Different aspects, with a direct influence on yield, such as the selection of chemicals including pH, ionic strength, additives, etc., and other often neglected aspects, important during scale-up, such as mixing, and gas-fluid interaction, are highlighted with the use of a quality by design (QbD) approach. The benefits of simulation sciences (process simulation and computer fluid dynamics) and process analytical technology (PAT) for seamless process development are emphasized. The work concludes with an outlook on future applications of refolding and highlights open research inquiries.

Fusion protein technologies improve the expression and purification of recombinant proteins, but the removal of the tags involved requires specific proteases. The circularly permuted caspase-2 (cpCasp2) with its specific cleavage site, efficiently generates the untagged protein. While cleavage with cpCasp2 is possible before all 20 proteinogenic amino acids, cleavage before valine, leucine, isoleucine, aspartate and glutamate suffers from slow, and before proline extremely slow, turnover. To make the platform fusion protein process even more general such that any protein with an authentic N-terminus can be produced with high efficiency, the bacterial selection system PROFICS (PRotease Optimization via Fusion-Inhibited Carbamoyltransferase-based Selection) was used to evolve cpCasp2 into a variant with a catalytic turnover two orders of magnitude higher and the ability to cleave before any amino acid. The high specificity and the stability of the original circularly permuted protease was fully retained in this mutant, while the high manufacturability was mostly retained, albeit with decreased soluble titer. Four point-mutations are responsible for this change in activity, two of which are located in or near the binding pocket of the active site. This variant was named CASPON enzyme and is a major component of the CASPase-based fusiON (CASPON) platform technology. Applicability for the production of recombinant proteins was demonstrated by enzymatic removal of the CASPON tag from five model proteins. The CASPON tag enables high soluble expressions, affinity purification and good accessibility for cleavage. The five industry-relevant proteins of interest were FGF2, TNF, GH, GCSF and PTH.

BACKGROUND: Recombinant proteins produced for use as biopharmaceuticals need to harbor their native N‐terminus. A drawback in expression of recombinant proteins as fusion proteins with an affinity fusion‐tag is that enzymatic or chemical processing is required to trim the artificial tag and release the true protein of interest. In many cases, however, this processing step generates an incorrect N‐terminus. RESULTS: Human fibroblast growth factor 2 (FGF2) was expressed as a fusion protein in Escherichia coli fed‐batch cultivations. The protein of interest (POI) carried an N‐terminal affinity fusion‐tag which enabled purification via affinity chromatography. After enzymatic removal of the affinity fusion‐tag with a circularly permuted human caspase‐2 (cpCasp2), the POI was further purified using subtractive affinity chromatography. Mass spectrometric analysis confirmed the authentic N‐terminus of the POI. The generated POI was highly pure with 42 ppm host cell protein, 3.7 μg mL⁻¹ dsDNA and ~ 1000 EU mL⁻¹ endotoxin. Only a small number of E. coli host cell proteins were co‐purified with the POI. Because of the high specificity of the novel protease cpCasp2, no off‐target cleavage could be observed. CONCLUSION: Our findings demonstrate that cpCasp2 can be used for the production of native proteins using a fusion‐protein process. This represents a first case study at large laboratory scale for the production of an industrially relevant protein. This technology constitutes the basis of a highly scalable cpCasp2‐based platform fusion protein process (CASPON technology) purification platform. © 2021 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.